1. Field of the Invention
The invention relates to a brake for a wheelchair, which has a pawl and an activation lever pivotally mounted within a support housing attached to a frame member of the wheelchair, and a leaf spring with a lancing detent, wherein each component acts together so as to provide a neutral position, a locked position, and an on-guard position which provides drag braking for downward inclines and a reverse braking aid for up-inclines.
2. Description of Related Art
Wheelchair brakes are known in the art. However, known prior art brakes are activated by a system of rods, or toothed gears or cams, and generally do not promote easy operation on both downward and upward inclines.
Known related art includes a three position brake using toothed cams depicted in a wheelchair patent, U.S. Pat. No. 4,101,143 to Seiber, a two position brake using a shoe against the wheel depicted in U.S. Pat. No. 4,350,227 to Knoche, and a three position brake using a toothed shoe depicted in U.S. Pat. No. 4,560,033 to DeWoody et al. Other known related wheelchair brakes include U.S. Pat. No. 4,570,756 to Minnebrake et al., U.S. Pat. No. 4,589,525 to Phipps et al., U.S. Pat. No. 4,691,933 to Strauss, U.S. Pat. No. 4,887,830 to Fought et al., U.S. Pat. No. 4,987,978 to Jungerson, U.S. Pat. No. 5,174,418 to Le et al., and U.S. Pat. No. 5,472,066 to Schello et al.
None of the devices in the above references solve the problem of providing an easy to operate brake which takes advantage of the long moment arm of the wheel in cooperative engagement with the short moment arm of a pawl to provide not only the normal neutral and locked position but to aid in braking in inclines, up and down. An object of this novel improvement to wheelchair brakes would provide a brake wherein gravity applied to the activation lever which engages the pawl can provide braking assistance for uphill and downhill modes of operation. Another object of the invention is to provide a brake which is simple and easy to operate and does not contain toothed cams which can break. A further object of the present invention is to provide a brake which prevents warping of the wheelchair framework by the application of equal and limited force.